Consolidated Statements of Income - USD ($) shares in Millions, $ in Millions		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenue
Lease Income		$ 266.5	$ 222.7	$ 194.6
Total revenue		13,409.1	12,552.9	15,056.9
Costs and expenses
Leases, Income Statement, Cost		167.9	143.4	137.2
Selling, general and administrative expense		1,228.1	1,140.6	1,060.9
Research and development expense		162.9	189.2	212.9
Impairment, restructuring and other expense (Note 20)		2,490.8	1,831.2	191.5
Merger transaction and integration costs (Note 2)		31.2	36.5	101.8
Total costs and expenses		14,935.8	13,470.5	14,091.7
Other income (expense), net		(220.7)	(323.9)	(25.9)
Income from equity affiliates (Note 12)		62.9	114.3	55.6
Income (loss) before interest income, interest expense and income taxes		(1,684.5)	(1,127.2)	994.9
Interest income		116.5	121.4	140.8
Interest expense		(567.8)	(482.3)	(456.0)
Income (loss) before income taxes	[1]	(2,135.8)	(1,488.1)	679.7
Provision for income taxes (Note 22)		276.3	422.7	545.5
Net income (loss)		(2,412.1)	(1,910.8)	134.2
Net profit attributable to noncontrolling interests		$ (3.1)	(10.8)	(20.9)
Net income (loss) attributable to TechnipFMC plc			$ (1,921.6)	$ 113.3
Earnings (loss) per share attributable to TechnipFMC plc (Note 8)
Basic earnings (loss) per share (usd per share)		$ (5.39)	$ (4.20)
Diluted earnings (loss) per share (usd per share)		$ (5.39)	$ (4.20)	$ 0.24
Weighted average shares outstanding (Note 8)
Basic (in shares)		448.0	458.0	466.7
Diluted (in shares)		448.0	458.0	468.3
Separation costs		$ 72.1	$ 0.0	$ 0.0
Service [Member]
Revenue
Revenue		9,789.7	9,057.6	11,445.9
Costs and expenses
Cost of product revenue		7,767.2	7,452.7	9,433.1
Product [Member]
Revenue
Revenue		3,352.9	3,272.6	3,416.4
Costs and expenses
Cost of product revenue		$ 3,015.6	$ 2,676.9	$ 2,954.3

[1] Includes amounts attributable to noncontrolling interests.